Just thought you guys might like a heads up.
The convertible dresses are generally flowy jersey dresses (full or knee length) that can be tied a lot of different ways so that bridesmaids can all personalize their dresses, and are in the $50 range -- elsewhere they're in the $150 range:
http://www.henkaa.com/convertible-dresses/sakura-long/
Here's an invite if you didn't get one last time: